1. Field of the Invention
This invention relates to aggregation pheromones of insects, particularly the driedfruit beetle Carpophilus hemipterus, and the use of these pheromones in combination with host plant volatiles to aid in insect control as, for example, in pheromone-baited traps.
2. References
Throughout this application, various publications are referenced by the name of the author and date of publication within parentheses. Full citations for these references may be found at the end of the specification, listed in alphabetical order.
3. Description of the Prior Art
Insect-produced volatiles (e.g., pheromones) and host plant odors (e.g., kairomones) may facilitate location of conspecifics for mating and orientation to acceptable host plants for feeding and oviposition. It is known that in several insect species (e.g., bark beetles) pheromones and plant odors, such as monoterpenes, may act in synergy, each enhancing the attraction of the other (Borden, 1984).
Carpophilus hemipterus (L.) (Coleoptera: Nitidulidae) is a worldwide pest, attacking agricultural commodities such as ripe and dried fruit, corn, wheat, oats, rice, beans, nuts, peanuts, cotton seed, copra, spices, sugar, honey, and other materials (Hinton, 1945). It is also able to vector microorganisms responsible for the souring of figs (Hinton, 1945) and fungi which contaminate corn and produce mycotoxins (Wicklow et al., 1988).
Field traps have been used to monitor or control this and other nitidulid species, and much research has gone into trap baits. Smilanick et al (1978) determined that a 1:1:1 mixture of acetaldehyde, ethyl acetate, and ethanol was an effective bait for C. hemipterus. Alm et al. (1985, 1986) demonstrated that esters such as propyl propionate and butyl acetate were effective baits for Glischrochilus quadrisignatus, another economically important nitidulid. In nature, these chemicals exist in the host plant, are produced by microorganisms which have established on the plants, or both. Curiously, no pheromones have been reported for nitidulid beetles, even though attractants of this type would probably be potent trap baits or additives to presently used baits; pheromones have been reported for a large number of other beetle species.